That's the same reason that Lloyd Dobler has in "Say Anything" for not wanting to volunteer at the old folks' home - the always chew with their mouths open, and make all kinds of weird noises while they chew. And Diane yells at him, saying that's ageism, and maybe they're mouths don't work as well as they used to. Then Lloyd does a 180 and goes down to the home. Talk about whipped.